But when Eric Stieler hears that 400 koi fish were recently taken from this Herndon Business Park pond, he and others were shocked.

According to Fairfax Police, on at least four occasions in June, two men posing as maintenance workers were seen scooping koi fish with large nets and placing them into large coolers before driving off in an SUV.

“Apparently, the people were very engaging,” says one officer.

And whenever the men were asked questions, they had an answer ready to go.

"They said that they worked with the pond maintenance company and that they were removing sick fish and leaving the healthy ones,” explains the cop.

After the fourth time however, some people got suspicious and called the property managers, who knew nothing about this supposed “fish maintenance.”

Depending on the size and color, koi fish can be worth anywhere from $400 to $2,000.

It turns out that many people did witness these men, but didn’t think twice about what they were doing.